Dual reflective liquid crystal display device
Summary by NHIP
Dual reflective LCD with stepped light guides
The device includes two substrates with outer polarizers, retardation layers, stepped light guide layers, and lateral auxiliary light sources. Inner reflective layers feature openings and convex-concave shapes to reflect light through the substrates, with the second layer matching or exceeding the first layer's opening size.
Claim Score by NHIP
Abstract
A liquid crystal display device includes a first substrate having a first polarizer and a first retardation layer; a second substrate having a second polarizer and a second retardation layer; and a pixel between the first and second substrates, the pixel having a thin film transistor, a first reflective layer on the first substrate, a second reflective layer on the second substrate, a liquid crystal layer between the first and second substrates.
Term
Projected expiry 10 October 2026.
- Priority
- Filed
- Granted
- Today
- Projected expiry
8 claims: 4 independent, 4 dependent
- 1A dual reflective liquid crystal display device comprising:a first substrate having a first polarizer and a first retardation layer, wherein the first polarizer and the first retardation layer are formed at an outer surface of the first substrate;a first light guide layer at an outer side of the first substrate, wherein the first light guide layer is provided with a step at one surface thereof;a first auxiliary light source formed at a lateral surface of the first substrate;a second substrate having a second polarizer and a second retardation layer, wherein the second polarizer and the second retardation layer are formed at an outer surface of the second substrate;a second light guide layer at an outer side of the second substrate, wherein the second light guide layer is provided with a step at one surface thereof;a second auxiliary light source formed at a lateral surface of the second substrate;and a pixel between the first and second substrates, the pixel having a thin film transistor, a first reflective layer on the first substrate, a second reflective layer on the second substrate, and the second retardation layer are formed at an outer surface of the second substrate, a liquid crystal layer between the first and second substrates, wherein the first reflection layer has an opening portion and a convex-concave shape to increase a reflection efficiency, and the second reflection layer corresponds to the opening portion of the first reflection layer, and the size of the second reflection layer is equal to or larger than the opening portion, wherein the second reflection layer is formed at an inner surface of the second substrate;wherein first light incident through the opening portion of the first reflective layer on the first substrate is reflected by the second reflective layer, to pass through the first substrate;and second light incident through the second substrate is reflected by the first reflective layer, to pass through the second substrate, and wherein the first and second auxiliary light sources are turned off when there is external light, and the first and second auxiliary light sources are turned on when there is no external light so that an user views image or information from both sides of the liquid crystal display device, and wherein the light provided from the first auxiliary light source incident through the first light guide layer is reflected by the second reflective layer so that a first image is viewed through the first light guide layer at an outer side of the first substrate, and the light provided from the second auxiliary light source incident through the second light guide layer is reflected by the first reflective layer so that a second image is viewed through the second light guide layer at an outer side of the second substrate, and the first image is the same image as the second image.
- 5A dual reflective liquid crystal display device comprising;a first substrate having a first reflective layer, wherein the first reflection layer has an opening portion and a convex-concave shape to increase a reflection efficiency;a first light guide layer at an outer side of the first substrate, wherein the first light guide layer is provided with a step at one surface thereof;a first auxiliary light source formed at a lateral surface of the first substrate;a second substrate having a second reflective layer and a color filter layer thereon, the color filter disposed over the second reflective layer, wherein the second reflection layer corresponds to the opening portion of the first reflection layer, and the size of the second reflection layer is equal to or larger than the opening portion, wherein the first and second substrates include first and second retardation films, respectively, and wherein the retardation films include a quarter wave plate;a second light guide layer at an outer side of the second substrate, wherein the second light guide layer is provided with a step at one surface thereof;a second auxiliary light source formed at a lateral surface of the second substrate;and a liquid crystal layer between the first and second substrates, wherein light reflected by the first reflective layer of first light incident on the first substrate is shielded, and light reflected by the second reflective layer of the first light incident on the first substrate is used for displaying first information, wherein light reflected by the second reflective layer of second light incident on the second substrate is shielded, and light reflected by the first reflective layer of the second light incident on the second substrate is used for displaying second information, and wherein the second information is substantially the same as the first information, and wherein the first and second auxiliary light sources are turned off when there is external light, and the first and second auxiliary light sources are turned on when there is no external light so that an user views image or information from both sides of the liquid crystal display device, and wherein the light provided from the first auxiliary light source incident through the first light guide layer is reflected by the second reflective layer so that a first image is viewed through the first light guide layer at an outer side of the first substrate, and the light provided from the second auxiliary light source incident through the second light guide layer is reflected by the first reflective layer so that a second image is viewed through the second light guide layer at an outer side of the second substrate, and the first image is the same image as the second image.
- 6A dual reflective liquid crystal display device having a display panel comprising:a first side of a transistor array substrate of a display panel having a first reflective layer, wherein the first reflection layer has an opening portion and a convex-concave shape to increase a reflection efficiency;and a first light guide layer at an outer side of the transistor array substrate, wherein the first light guide layer is provided with a step at one surface thereof;a first auxiliary light source formed at a lateral surface of the transistor array substrate;a second side of a color filter array substrate of the display panel having a second reflective layer and a color filter layer thereon, the color filter layer disposed over the second reflective layer, a second light guide layer at an outer side of the color filter array substrate, wherein the second light guide layer is provided with a step at one surface thereof;a second auxiliary light source formed at a lateral surface of the color filter array substrate;wherein the second reflection layer corresponds to the opening portion of the first reflection layer, and the size of the second reflection layer is equal to or larger than the opening portion, wherein the first side of the transistor array substrate of the display panel displays first information using first light reflected from the second reflective layer, and the second side of the color filter array substrate of the display panel displays second information using second light reflected from the first reflective layer, wherein the first light is incident through the transistor array substrate, and the second light is incident through the color filter array substrate;and wherein the first information is substantially the same as the second information, and wherein the first and second auxiliary light sources are turned off when there is external light, and the first and second auxiliary light sources are turned on when there is no external light so that an user views image or information from both sides of the display panel, and wherein the light provided from the first auxiliary light source incident through the first light guide layer is reflected by the second reflective layer so that a first image is viewed through the first light guide layer at an outer side of the first substrate, and the light provided from the second auxiliary light source incident through the second light guide layer is reflected by the first reflective layer so that a second image is viewed through the second light guide layer at an outer side of the second substrate, and the first image is the same image as the second image.
- 8Broadest claimClaim Score 19, narrow(NHIP)A dual reflective liquid crystal display device having a display panel comprising:a transistor array substrate having a first reflective plate;a color filter substrate having a second reflection plate and a color filter layer thereon, the color filter layer disposed over the second reflective plate;a first auxiliary light source formed at a lateral surface of the transistor array substrate;a first light guide plate for reflecting light generated from the first auxiliary light source to a liquid crystal layer, wherein the first light guide plate is provided with a step at one surface thereof to completely reflect light introduce from the first auxiliary light source to the liquid crystal layer;a second auxiliary light source formed at a lateral surface of the color filter substrate;and a second light guide plate for reflecting light generated from the second auxiliary light source to the liquid crystal layer, wherein the second light guide plate is provided with a step at one surface thereof to completely reflect light introduce from the second auxiliary light source to the liquid crystal layer, wherein light introduced from the first auxiliary light source is reflected by the second reflection plate, and light introduced from the second auxiliary light source is reflected by the first reflection plate, and wherein the first and second auxiliary light sources are turned off when there is external light, and the first and second auxiliary light sources are turned on when there is no external light so that an user views image or information from both sides of the liquid crystal display device, and wherein the light provided from the first auxiliary light source incident through the first light guide layer is reflected by the second reflective layer so that a first image is viewed through the first light guide layer at an outer side of the first substrate, and the light provided from the second auxiliary light source incident through the second light guide layer is reflected by the first reflective layer so that a second image is viewed through the second light guide layer at an outer side of the second substrate, and the first image is the same image as the second image.
Independent claims4
58 paragraphs in 4 sections, as filed
This application claims the benefit of Korean Patent Application No. 2003-94290, filed on Dec. 20, 2003, which is hereby incorporated by reference for all purposes as if fully set forth herein.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a reflective liquid crystal display (LCD) device, and more particularly, to a dual-reflective LCD device and a method for fabricating the same that can display the same information at both surfaces thereof.
2. Discussion of the Related Art
A liquid crystal display (LCD) device is one of the most spotlighted display devices, and is being widely used as an image display device applied to various products such as TV monitors, computer monitors, mobile phones, etc. Especially, a reflective LCD device, which may use external light, is used for mobile electronic devices, because it carries a screen with a thin film and consumes less power.
Hereinafter, a structure of a reflective LCD device according to a related art will be explained with reference to <figref idrefs="DRAWINGS">FIG. 1</figref>.
The reflective LCD device includes a TFT (Thin Film Transistor) array substrate where a thin film transistor (TFT) is formed, and a color filter substrate where a color filter layer is formed. A liquid crystal layer is filled between the TFT array substrate and the color filter substrate. The TFT array substrate includes a transparent substrate <b>101</b>, a plurality of gate lines (not shown) formed on the substrate, and a plurality of data lines <b>104</b> crossing the gate lines, a TFT <b>150</b> formed near the crossing region between the gate lines and the data lines <b>104</b>, a passivation layer <b>103</b> formed of an organic layer or an inorganic layer, which protect the TFT, and a reflective layer <b>105</b> formed on the passivation layer. The color filter substrate includes a substrate <b>110</b>, a black matrix <b>109</b> formed on the substrate, a color filter layer <b>108</b> formed on the substrate, and a common electrode <b>107</b> formed on the color filter layer.
The reflective LCD may further include a spacer (not shown) for maintaining a cell gap between the TFT array substrate and the color filter substrate, and an alignment layer (not shown) for an alignment of liquid crystal. A liquid crystal layer <b>106</b> having a dielectric constant and a refractive anisotropy is formed between the TFT array substrate and the color filter substrate. The TFT array substrate and the color filter substrate are assembled to each other by a sealant (not shown) formed at a peripheral portion of the display region, thereby forming a reflective LCD panel.
When external light is irradiated on the reflective LCD device, the external light passes through the upper color filter substrate and the liquid crystal layer <b>106</b>, and then is reflected by the reflection layer <b>105</b> formed on the TFT array substrate.
However, in the reflective LCD device, since images are displayed only on one surface of the LCD device, users can not view the images from the opposite direction. To solve this disadvantage of the reflective LCD device, a method is proposed in which a reflective LCD device has two LCD panels bonded together. However, because such a reflective LCD device has two LCD panels, the structure becomes complicated and the production cost increases.
SUMMARY OF THE INVENTION
Accordingly, the present invention is directed to a dual-reflective liquid crystal display device that substantially obviate one or more of the problems due to limitations and disadvantages of the related art.
An advantage of the present invention is to provide a dual-reflective LCD device that can display the same information at both surfaces of a transparent substrate.
Another advantage of the present invention is to provide a dual-reflective LCD device capable of reducing fabrication costs by using one liquid crystal layer.
Still another advantage of the present invention is to provide a dual-reflective LCD device capable of being operated without an external light source.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described, a liquid crystal display device includes a first substrate having a first polarizer and a first retardation layer; a second substrate having a second polarizer and a second retardation layer; and a pixel between the first and second substrates, the pixel having a thin film transistor, a first reflective layer on the first substrate, a second reflective layer on the second substrate, a liquid crystal layer between the first and second substrates.
The LCD device further includes an auxiliary light source.
In another aspect of the present invention, a liquid crystal display device includes a first substrate having a first reflective layer; a second substrate having a second reflective layer; and a liquid crystal layer between the first and second substrates, wherein the light reflected by the first reflective layer of light incident on the first substrate is shielded, and the light reflected by the second reflective layer of light incident on the first substrate is used for displaying first information, wherein the light reflected by the second reflective layer of light incident on the second substrate is shielded, and the light reflected by the first reflective layer of light incident on the second substrate is used for displaying second information, and wherein the second information is substantially the same as the first information.
In still another aspect of the present invention, a display device having a display panel includes a first side of the display panel having a first reflective layer; and a second side of the display panel having a second reflective layer, wherein the first side of the display panel displays first information using the light reflected from the second reflective layer, and the second side of the display panel displays second information using the light reflected from the first reflective layer, wherein the first information is substantially the same as the second information.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention.
In the drawings:
<figref idrefs="DRAWINGS">FIG. 1</figref> is a sectional view illustrating a structure of a reflective LCD device according to a related art;
<figref idrefs="DRAWINGS">FIG. 2</figref> is a sectional view illustrating a dual-reflective LCD device according to the first embodiment of the present invention;
<figref idrefs="DRAWINGS">FIG. 3</figref> is a plan view illustrating the dual reflective LCD device of <figref idrefs="DRAWINGS">FIG. 2</figref>;
<figref idrefs="DRAWINGS">FIG. 4</figref> is a sectional view taken along the line I-I′ of <figref idrefs="DRAWINGS">FIG. 3</figref>, illustrating a structure of a TFT according to the present invention;
<figref idrefs="DRAWINGS">FIG. 5</figref> is a sectional view taken along the line II-II′ of <figref idrefs="DRAWINGS">FIG. 3</figref>, illustrating a structure of a storage capacitor according to the present invention;
<figref idrefs="DRAWINGS">FIGS. 6A and 6B</figref> are schematic views illustrating an operating principle of a dual-reflective LCD device according to the present invention; and
<figref idrefs="DRAWINGS">FIG. 7</figref> is a schematic sectional view illustrating a dual-reflective LCD device according to the second embodiment of the present invention.
DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS
Reference will now be made in detail to the embodiments of the present invention, examples of which are illustrated in the accompanying drawings.
Hereinafter, a structure of a dual-reflective liquid crystal display (LCD) device according to a first embodiment of the present invention will be explained with reference to <figref idrefs="DRAWINGS">FIGS. 2 and 3</figref>. <figref idrefs="DRAWINGS">FIG. 2</figref> is a sectional view illustrating a dual-reflective LCD device according to the first embodiment of the present invention, and <figref idrefs="DRAWINGS">FIG. 3</figref> is a plan view illustrating the dual reflective LCD device of <figref idrefs="DRAWINGS">FIG. 2</figref>.
Referring to <figref idrefs="DRAWINGS">FIGS. 2 and 3</figref>, a dual-reflective LCD device according to the first embodiment of the present invention includes a TFT (Thin Film Transistor) array substrate and a color filter substrate facing each other. A liquid crystal layer <b>217</b> is formed between the TFT array substrate and the color filter substrate.
The TFT array substrate includes a first transparent substrate <b>203</b> having a plurality of TFTs <b>208</b>. A first polarizer <b>201</b> for polarizing incident light and a first retardation film <b>202</b> for phase-delaying light polarized by the first polarizer <b>201</b> are formed at an outer side of the first substrate <b>203</b>. The first retardation film <b>202</b> is formed between the first transparent substrate <b>203</b> and the first polarizer <b>201</b>. The TFTs <b>208</b> are arranged in a matrix configuration on the first substrate <b>203</b> as a switching device for switching unit pixels. A plurality of gate lines <b>301</b> and a plurality of data lines <b>205</b> crossing the gate lines are further formed on the first substrate <b>203</b>. The TFTs <b>208</b> are formed near the crossing between the gate lines and the data lines, and a unit pixel region is defined by the gate lines <b>301</b> and the data lines <b>205</b>.
The array substrate further includes a passivation layer <b>206</b> of an organic material or an inorganic material for protecting the TFTs, and a first reflection layer <b>207</b> for reflecting incident light formed on the passivation layer <b>206</b>. Each unit pixel has the first reflection layer <b>207</b>, which is connected to the TFT <b>208</b> through a contact hole in the passivation layer <b>206</b>.
The first reflection layer <b>207</b> in a unit pixel has an opening portion <b>216</b><i>a</i>, as illustrated in <figref idrefs="DRAWINGS">FIG. 3</figref>. Through the opening portion <b>216</b><i>a</i>, light incident from a lower portion reaches the upper color filter layer. The opening portion <b>216</b><i>a </i>may be formed at a center region of the first reflection layer <b>207</b> with a predetermined size. Light reflected through the opening portion <b>216</b><i>a </i>enables a user to view images in one direction of the dual-reflective LCD device of the present invention. When determining the size of the opening portion <b>216</b><i>a</i>, the aperture ratio, brightness, and other characteristics of the dual-reflective LCD should be taken into consideration. The first reflection layer <b>207</b> may have a convex-concave shape to increase the reflectivity. The first reflection layer having a convex-concave shape can collect light in the user direction, and reflect light uniformly to all directions to achieve uniform picture quality.
Still referring to <figref idrefs="DRAWINGS">FIGS. 2 and 3</figref>, the color filter substrate includes a second transparent substrate <b>212</b>, a second reflection layer <b>216</b>, a second retardation film <b>211</b>, a color filter layer <b>213</b>, a common electrode <b>215</b> and a second polarizer <b>210</b>. The second polarizer <b>210</b> polarizes light incident on an outer surface the second substrate <b>212</b>, and the second retardation film <b>211</b> delays the phase of the polarized light. The second reflection layer <b>216</b> reflects light incident from a direction of the TFT array substrate, the color filter layer <b>213</b> is used for displaying color images, and the common electrode <b>215</b> of a transparent conductive material applies an electric field to the liquid crystal layer <b>217</b>. The color filter layer <b>213</b> has sub-color filter layers of R, G, and B, and the three R, G and B sub-color filters constitute one unit pixel.
The second reflection layer <b>216</b> in a unit pixel is formed on the color filter substrate, corresponding to the opening portion <b>216</b><i>a </i>of the first reflection layer <b>207</b>. That is, light passing through the opening portion <b>216</b><i>a </i>of the first reflection layer <b>207</b> is reflected by the second reflection layer <b>216</b>, and is then emitted in a direction of the TFT array substrate. Therefore, the size of the second reflection layer <b>216</b> may be equal to or larger than the opening portion <b>216</b><i>a. </i>
Referring to <figref idrefs="DRAWINGS">FIG. 3</figref>, the TFT <b>208</b> is formed near the crossing between the gate line <b>301</b> and the data line <b>205</b>. The first reflection layer <b>207</b> connected to the drain electrode of the TFT <b>208</b> is formed in the unit pixel region. The opening portion <b>216</b><i>a </i>is formed at a center region of the first reflection layer <b>207</b>. Through the opening portion <b>216</b><i>a</i>, light incident from an outside of the TFT array substrate reaches the second reflection layer <b>216</b>. The second reflection layer <b>216</b> is formed to correspond to the opening portion <b>216</b><i>a </i>of the first reflection layer <b>207</b>, and the size of the second reflection layer <b>216</b> may be equal to or larger than the opening portion <b>216</b><i>a. </i>
A structure of a TFT according to the present invention will be explained with reference to <figref idrefs="DRAWINGS">FIG. 4</figref>. <figref idrefs="DRAWINGS">FIG. 4</figref> is a sectional view taken along the line I-I′ of <figref idrefs="DRAWINGS">FIG. 3</figref>, illustrating a structure of a TFT according to the present invention.
The TFT of the LCD device according to the present invention includes a gate electrode <b>401</b> formed on the substrate <b>203</b>, a gate insulating layer <b>204</b> formed on the substrate where the gate electrode <b>401</b> is formed, a semiconductor layer <b>402</b> formed on the gate insulating layer <b>204</b>, a second semiconductor layer <b>403</b> formed on the semiconductor layer at a region except a channel layer and into which a high concentration impurity ion is injected, source and drain electrodes <b>404</b> and <b>405</b> ohmic-contacting the second semiconductor layer <b>403</b>, the passivation layer <b>206</b> for protecting the device, and the first reflection layer <b>207</b> connected to the drain electrode <b>405</b>. The source electrode is connected to the data line <b>205</b>, and the TFT drives a pixel by gate and data signals.
A structure of a storage capacitor will be explained with reference to <figref idrefs="DRAWINGS">FIG. 5</figref>. <figref idrefs="DRAWINGS">FIG. 5</figref> is a sectional view taken along the line II-II′ of <figref idrefs="DRAWINGS">FIG. 3</figref>, illustrating a structure of a storage capacitor according to the present invention. <figref idrefs="DRAWINGS">FIG. 5</figref> illustrates a storage on gate (SOG) type capacitor in which a capacitor structure is formed on a gate line.
A gate line <b>501</b> is formed on the substrate <b>203</b>, and the gate insulating layer <b>204</b> is formed on the gate line. Also, a storage electrode <b>502</b> is formed on the gate insulating layer <b>204</b>, over the gate line <b>501</b>. The storage electrode <b>502</b> is connected to the first reflection layer <b>207</b> formed on the passivation layer <b>206</b>, thereby forming a storage capacitor.
Hereinafter, an operational principle of the dual reflective LCD device of the present invention will be explained. <figref idrefs="DRAWINGS">FIGS. 6A and 6B</figref> are schematic views illustrating an operating principle of a dual-reflective LCD device according to the present invention.
First, an operational principle with respect to light incident on the array substrate will be explained with reference to <figref idrefs="DRAWINGS">FIGS. 6A and 6B</figref>. Some of the light incident on the array substrate is reflected by the first reflection layer <b>207</b> and thus is shielded by the first polarizer <b>201</b>. Some of the light incident on the array substrate is reflected by the second reflection layer <b>216</b> and thus passes through the TFT array substrate.
Referring to <figref idrefs="DRAWINGS">FIG. 6A</figref>, among light incident on the array substrate, only a linearly-polarized light parallel to a polarization axis of the first polarization layer <b>201</b> passes through the first polarization layer <b>201</b>. The linearly-polarized light is phase-delayed by the first retardation film <b>202</b> to become right circularly polarized light. Therefore, the first retardation film <b>202</b> may be a quarter wave plate for phase-delaying light by 90°. The right circularly polarized light is reflected by the first reflection layer <b>207</b>, and thus is converted into left circularly polarized light. The left circularly polarized light passes through the first retardation film <b>202</b>, and thus is converted into a linearly-polarized light perpendicular to the polarization axis of the first polarizer <b>201</b>. Therefore, this linearly-polarized light is shielded by the first polarizer <b>201</b>.
Referring to <figref idrefs="DRAWINGS">FIG. 6B</figref>, the light passing through the opening portion of the first reflection layer among the light incident on the TFT array substrate is right circularly polarized light, as explained above. The right circularly polarized light then passes through the liquid crystal layer <b>217</b> and thus becomes a linearly-polarized light perpendicular to the linearly-polarized light by the first polarizer <b>201</b>. The linearly-polarized light is then reflected by the second reflection layer <b>216</b> and again passes through the liquid crystal layer <b>217</b>, and thus becomes right circularly polarized light. The right circularly polarized light passes through the first retardation film <b>202</b> and thus becomes a linearly-polarized light parallel to the polarization axis of the first polarizer <b>201</b>. Therefore, this linearly-polarized light passes through the first polarizer <b>201</b>. That is, the right circularly polarized light becomes white.
In the above explanation, it is assumed that the polarized light passes through the liquid crystal layer in a direction perpendicular to the long axis of the liquid crystal molecules of the liquid crystal layer. Thus, gray levels can be obtained by applying different voltages between the two substrates to control the direction of the long axis of the liquid crystal molecules.
Next, light incident on the color filter substrate will be explained. Light incident on the color filter substrate is also reflected or shielded in accordance with the operational principle discussed with reference to <figref idrefs="DRAWINGS">FIGS. 6A and 6B</figref>.
That is, among light incident on the color filter substrate from outside, the light reflected by the second reflection layer <b>216</b> sequentially passes through the second polarizer <b>210</b>, the second retardation film <b>211</b>, the second reflection layer <b>216</b>, the second retardation film <b>211</b>, and the second polarizer <b>210</b> and thus is shielded (the dotted line <b>231</b> of <figref idrefs="DRAWINGS">FIG. 2</figref>). The second retardation film <b>211</b> may be a quarter wave plate.
Among light incident on the color filter substrate from outside, the light reflected by the first reflection layer <b>207</b> sequentially passes through the second polarizer <b>210</b>, the second retardation film <b>211</b>, the liquid crystal layer <b>217</b>, the first reflection layer <b>207</b>, the liquid crystal layer <b>217</b>, the second retardation film <b>211</b>, and the second polarizer <b>210</b> (the solid line <b>230</b> of <figref idrefs="DRAWINGS">FIG. 2</figref>). Thus, the light reflected by the first reflection layer <b>207</b> can pass through or is shielded by the color filter substrate, depending on the direction of the light when passing through the liquid crystal layer. That is, as explained with respect to the light incident on the TFT array substrate, when the polarized light passes through the liquid crystal layer in a direction perpendicular to the long axis of the liquid crystal molecules, the polarized light becomes white (the solid line <b>230</b>).
Accordingly, the user can view the same information from both sides of the dual-reflective LCD device. However, according to the dual-reflective LCD device of the first embodiment, the user can view information from both directions only with external light. To solve such a problem, a dual-reflective LCD device according to a second embodiment of the present invention includes an auxiliary light source so that it can be used when there is no external light source.
A dual-reflective LCD device according to the second embodiment of the present invention is provided with a first auxiliary light source and a second auxiliary light source outside first and second polarizers. The TFT array substrate of the second embodiment has the same structure as that of the first embodiment. A structure of a dual-reflective LCD device according to the second embodiment of the present invention will be explained with reference to <figref idrefs="DRAWINGS">FIG. 7</figref>.
Referring to <figref idrefs="DRAWINGS">FIG. 7</figref>, an LCD device according to the second embodiment of the present invention includes a TFT array substrate <b>601</b> having a first reflection layer <b>602</b>, a color filter substrate <b>603</b> having a second reflection layer <b>604</b>, a first auxiliary light source <b>606</b> formed at a lateral surface of the TFT array substrate, a first light guide layer <b>608</b> for reflecting the light generated from the first auxiliary light source <b>606</b> to a liquid crystal layer <b>605</b>, a second auxiliary light source <b>607</b> formed at a lateral surface of the color filter substrate <b>603</b>, and a second light guide layer <b>609</b> for reflecting the light generated from the second auxiliary light source <b>607</b> to the liquid crystal layer <b>605</b>. The TFT array substrate and the color filter substrate have the same constructions as those of the first embodiment of the present invention. The first auxiliary light source <b>606</b> and the second auxiliary light source <b>607</b> may generate white light close to natural light.
The first and second auxiliary light sources can be installed at lateral surfaces of the TFT array substrate and the color filter substrate. Each auxiliary light source is connected to an inverter (not shown) for supplying power to the light source, and is further provided with a switch (not shown) for selectively turning on/off the light source. The first light guide layer <b>608</b> is installed at an inner surface of the TFT array substrate in order to introduce the light generated from the first auxiliary light source <b>606</b> into the liquid crystal layer <b>605</b>, and the second light guide layer <b>609</b> is installed at an inner surface of the color filter substrate to introduce the light generated from the second auxiliary light source <b>607</b> into the liquid crystal layer <b>605</b>.
The first light guide layer <b>608</b> and the second light guide layer <b>609</b> can be provided with a step on one surface thereof to increase reflectivity of the light introduced from the light source. Another surface of the first light guide layer <b>608</b> and the second light guide layer <b>609</b> may have a flat surface.
According to the present invention, the LCD device may turn off the auxiliary light sources when there is external light, and turn on the auxiliary light sources when there is no or insufficient external light. Accordingly, the LCD device can be effectively used regardless of external light conditions.
As aforementioned, with the dual-reflective LCD device according to the present invention, the user can view the same image or information from both sides of the liquid crystal panel. Also, because an auxiliary light source is provided, the LCD device can be effectively used regardless of external light conditions. Additionally, because the dual-reflective LCD device has only one liquid crystal panel, the fabrication cost can be reduced.
It will be apparent to those skilled in the art that various modifications and variations can be made in the above-discussed display device and the driving method thereof without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.
Contents4
6 sheets
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Every citation, both ways
| Document | Relation | Office | Cited during |
|---|---|---|---|
| US2008100601A1 | Cited by | United States of America | Pre-grant |
| US10728413B2 | Cited by | United States of America | Applicant |
| US10334133B2 | Cited by | United States of America | Search report |
| US8462295B2 | Cited by | United States of America | Search report |
| US2010253878A1 | Cited by | United States of America | Pre-grant |
| CN1195118A | Cites | China | Applicant |
| CN1195119A | Cites | China | Applicant |
| CN1438529A | Cites | China | Applicant |
| JP2002357825A | Cites | Japan | Applicant |
| US2003063243A1 | Cites | United States of America | Search report |
| JP2003161945A | Cites | Japan | Applicant |
| US2003174270A1 | Cites | United States of America | Applicant |
| US2003210366A1 | Cites | United States of America | Search report |
| US2005046768A1 | Cites | United States of America | Search report |
| US4158484A | Cites | United States of America | Search report |
| US6064456A | Cites | United States of America | Search report |
| US6295109B1 | Cites | United States of America | Search report |
| US6347874B1 | Cites | United States of America | Search report |
| US6897914B2 | Cites | United States of America | Search report |
6 members in 3 offices
Priority claims4
| Document | Office | Kind | Date |
|---|---|---|---|
| 20030094290 | Republic of Korea | A | |
| 20030094290 | Republic of Korea | A | |
| 1020030094290 | – | – | – |
| KR20030094290 | – | – | – |
Members6
| Document | Office | Kind | |
|---|---|---|---|
| CN1629700A | China | A | |
| KR20050062269A | Republic of Korea | A | |
| US2005134767A1 | United States of America | A1 | |
| CN100343738C | China | C | |
| CN101059634A | China | A | |
| US7889288B2This record | United States of America | B2 |
99 transactions on the USPTO file
Allowed after 4 non-final rejections, 3 final rejections and 3 RCEs.
- Non-final rejections
- 4
- Final rejections
- 3
- RCEs
- 3
- Appeals
- 0
Over time
Point at a mark for the transactionTransactions
| Event | Code | |
|---|---|---|
| Expire PatentEXP. | EXP. | |
| Maintenance Fee Reminder MailedREM. | REM. | |
| Payment of Maintenance Fee, 8th Year, Large EntityM1552 | M1552 | |
| Recordation of Patent Grant MailedPGM/ | PGM/ | |
| Patent Issue Date Used in PTA CalculationAllowedPTAC | PTAC | |
| Issue Notification MailedAllowedWPIR | WPIR | |
| Dispatch to FDCD1935 | D1935 | |
| Application Is Considered Ready for IssuePILS | PILS | |
| Issue Fee Payment VerifiedN084 | N084 | |
| Issue Fee Payment ReceivedIFEE | IFEE | |
| Mail Miscellaneous Communication to ApplicantMM327 | MM327 | |
| Miscellaneous Communication to Applicant - No Action CountM327 | M327 | |
| Information Disclosure Statement consideredIDSC | IDSC | |
| Information Disclosure Statement (IDS) FiledWIDS | WIDS | |
| Information Disclosure Statement (IDS) FiledM844 | M844 | |
| Mail Notice of AllowanceAllowedMN/=. | MN/=. | |
| Notice of Allowance Data Verification CompletedAllowedN/=. | N/=. | |
| Case Docketed to Examiner in GAUDOCK | DOCK | |
| Date Forwarded to ExaminerFWDX | FWDX | |
| Disposal for a RCE / CPA / R129AbandonedABN9 | ABN9 | |
| Request for Continued Examination (RCE)RCEX | RCEX | |
| Workflow - Request for RCE - BeginBRCE | BRCE | |
| Information Disclosure Statement consideredIDSC | IDSC | |
| Information Disclosure Statement (IDS) FiledM844 | M844 | |
| Information Disclosure Statement (IDS) FiledWIDS | WIDS | |
| Mail Final Rejection (PTOL - 326)Final rejectionMCTFR | MCTFR | |
| Final RejectionFinal rejectionCTFR | CTFR | |
| Mail Miscellaneous Communication to ApplicantMM327 | MM327 | |
| Date Forwarded to ExaminerFWDX | FWDX | |
| Miscellaneous Communication to Applicant - No Action CountM327 | M327 | |
| Workflow - Request for RCE - FinishFRCE | FRCE | |
| Response after Non-Final ActionA... | A... | |
| Improper Request for Continued ExaminationIRCE | IRCE | |
| Workflow - Request for RCE - BeginBRCE | BRCE | |
| Mail Non-Final RejectionNon-final rejectionMCTNF | MCTNF | |
| Non-Final RejectionNon-final rejectionCTNF | CTNF | |
| Date Forwarded to ExaminerFWDX | FWDX | |
| Date Forwarded to ExaminerFWDX | FWDX | |
| Disposal for a RCE / CPA / R129AbandonedABN9 | ABN9 | |
| Request for Continued Examination (RCE)RCEX | RCEX | |
| Workflow - Request for RCE - BeginBRCE | BRCE | |
| Mail Supplemental Final RejectionFinal rejectionMSFR. | MSFR. | |
| Supplemental Final RejectionFinal rejectionSFR. | SFR. | |
| Information Disclosure Statement (IDS) FiledM844 | M844 | |
| Information Disclosure Statement consideredIDSC | IDSC | |
| Information Disclosure Statement (IDS) FiledWIDS | WIDS | |
| Mail Final Rejection (PTOL - 326)Final rejectionMCTFR | MCTFR | |
| Final RejectionFinal rejectionCTFR | CTFR | |
| Date Forwarded to ExaminerFWDX | FWDX | |
| Information Disclosure Statement consideredIDSC | IDSC | |
| Response after Non-Final ActionA... | A... | |
| Request for Extension of Time - GrantedXT/G | XT/G | |
| Information Disclosure Statement (IDS) FiledM844 | M844 | |
| Information Disclosure Statement (IDS) FiledWIDS | WIDS | |
| Mail Non-Final RejectionNon-final rejectionMCTNF | MCTNF | |
| Non-Final RejectionNon-final rejectionCTNF | CTNF | |
| Date Forwarded to ExaminerFWDX | FWDX | |
| Date Forwarded to ExaminerFWDX | FWDX | |
| Disposal for a RCE / CPA / R129AbandonedABN9 | ABN9 | |
| Request for Continued Examination (RCE)RCEX | RCEX | |
| Request for Extension of Time - GrantedXT/G | XT/G | |
| Workflow - Request for RCE - BeginBRCE | BRCE | |
| Mail Advisory Action (PTOL - 303)MCTAV | MCTAV | |
| Advisory Action (PTOL-303)CTAV | CTAV | |
| Date Forwarded to ExaminerFWDX | FWDX | |
| Information Disclosure Statement consideredIDSC | IDSC | |
| Reference capture on IDSRCAP | RCAP | |
| Information Disclosure Statement (IDS) FiledM844 | M844 | |
| Information Disclosure Statement (IDS) FiledWIDS | WIDS | |
| Response after Final ActionA.NE | A.NE | |
| Mail Final Rejection (PTOL - 326)Final rejectionMCTFR | MCTFR | |
| Final RejectionFinal rejectionCTFR | CTFR | |
| Date Forwarded to ExaminerFWDX | FWDX | |
| Response after Non-Final ActionA... | A... | |
| Mail Non-Final RejectionNon-final rejectionMCTNF | MCTNF | |
| Non-Final RejectionNon-final rejectionCTNF | CTNF | |
| Date Forwarded to ExaminerFWDX | FWDX | |
| Response after Non-Final ActionA... | A... | |
| Mail Non-Final RejectionNon-final rejectionMCTNF | MCTNF | |
| Non-Final RejectionNon-final rejectionCTNF | CTNF | |
| Information Disclosure Statement consideredIDSC | IDSC | |
| Reference capture on IDSRCAP | RCAP | |
| Information Disclosure Statement (IDS) FiledM844 | M844 | |
| Information Disclosure Statement (IDS) FiledWIDS | WIDS | |
| Case Docketed to Examiner in GAUDOCK | DOCK | |
| Case Docketed to Examiner in GAUDOCK | DOCK | |
| Case Docketed to Examiner in GAUDOCK | DOCK | |
| Case Docketed to Examiner in GAUDOCK | DOCK | |
| Correspondence Address ChangeC.ADB | C.ADB | |
| IFW TSS Processing by Tech Center CompleteTSSCOMP | TSSCOMP | |
| Case Docketed to Examiner in GAUDOCK | DOCK | |
| Application Return from OIPEWROIPE | WROIPE | |
| Application Return TO OIPEROIPE | ROIPE | |
| Application Dispatched from OIPEOIPE | OIPE | |
| Application Is Now CompleteCOMP | COMP | |
| Cleared by OIPE CSRL194 | L194 | |
| IFW Scan & PACR Auto Security ReviewSCAN | SCAN | |
| Request for Foreign Priority (Priority Papers May Be Included)RQPR | RQPR | |
| Initial Exam Team nnIEXX | IEXX |
12 legal events, as the office reported them to INPADOC
Over the term
Point at a mark for the eventEvents
| Event | Code | |
|---|---|---|
| Lapsed due to failure to pay maintenance feeLapsedFP | FP | |
| Lapse for failure to pay maintenance feesLapsedPATENT EXPIRED FOR FAILURE TO PAY MAINTENANCE FEES (ORIGINAL EVENT CODE: EXP.); ENTITY STATUS OF PATENT OWNER: LARGE ENTITYLAPS | LAPS | |
| Information on status: patent discontinuationPATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362STCH | STCH | |
| Fee payment procedureMAINTENANCE FEE REMINDER MAILED (ORIGINAL EVENT CODE: REM.); ENTITY STATUS OF PATENT OWNER: LARGE ENTITYFEPP | FEPP | |
| Maintenance fee paymentMAFP | MAFP | |
| Fee paymentFPAY | FPAY | |
| Fee payment procedurePAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITYFEPP | FEPP | |
| Fee payment procedurePAYER NUMBER DE-ASSIGNED (ORIGINAL EVENT CODE: RMPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITYFEPP | FEPP | |
| Information on status: patent grantGrantedPATENTED CASESTCF | STCF | |
| AssignmentAS | AS | |
| AssignmentAS | AS | |
| AssignmentAS | AS |
Numbers
- Publication
- 07889288
- Publication, DOCDB
- 7889288
- Publication, EPODOC
- US7889288
- Application
- 11012124
- Application, DOCDB
- 1212404
- Application, EPODOC
- US20040012124
Titles
- English
- Dual reflective liquid crystal display device
Patent term adjustment
- A delay
- +456 daysthe office missed an examination deadline
- B delay
- +277 dayspendency past three years
- Applicant delay
- −70 days
- Net adjustment
- 663 days
Classification
- CPC, 5
- G02F1/1343
- G02F1/1347
- G02F2203/02
- G02F1/133342
- G02F1/133616
- IPC, 5
- G02F1 1335
- G02F1 133
- G02F1 1347
- G02F1 13357
- G02F1 1343
- USPC, 3
- 349061000
- 349065000
- 349113000